The recent news that the U.S. Department of Justice is investigating major prediction market platforms has sent shockwaves through the trading community. This probe, reportedly targeting firms like Kalshi and Polymarket for potential gambling law violations, directly threatens the already uncertain tax treatment of winnings and could force a major reclassification from capital gains to less favorable gambling income for thousands of traders.

DOJ Investigates Prediction Markets: What We Know

In April 2026, reports emerged that the Department of Justice has launched a probe into the rapidly growing prediction market industry. The investigation is said to be focused on whether these platforms are operating as unlicensed money transmitters or are in violation of federal gambling statutes, such as the Unlawful Internet Gambling Enforcement Act (UIGEA) and the Wire Act.

While details are still emerging, the core of the investigation appears to challenge the fundamental legal premise on which many of these platforms operate. Regulated platforms like Kalshi have long argued they are financial exchanges offering derivative contracts under the oversight of the Commodity Futures Trading Commission (CFTC). Decentralized crypto platforms like Polymarket function as on-chain protocols where users trade tokens representing the outcome of events. The DOJ's involvement suggests federal law enforcement may view these activities not as financial trading, but simply as betting.

It is crucial to remember that this is an investigation, not a final judgment. However, the probe alone introduces significant regulatory risk and casts a long shadow over the tax reporting strategies that traders have used for years.

The Unsettled Tax Landscape: Gambling, Capital Gains, or Section 1256?

The DOJ investigation brings a simmering debate to a boil: how exactly should prediction market profits be taxed? The IRS has yet to issue specific guidance, leaving traders and tax professionals to interpret existing rules. Currently, there are three main defensible positions, each with vastly different financial outcomes.

Treatment 1: Capital Gains

For traders on crypto-native platforms like Polymarket, treating trades as capital gains has been the standard approach. In this view, every trade is a disposition of a crypto asset (e.g., selling USDC to acquire a contract token).

Tax Rate: Gains are either short-term or long-term.
- Short-Term: If you hold the position for one year or less, the gain is taxed at your ordinary income tax rate. For the 2025 tax year, these rates range from 10% to 37% irs.gov.
- Long-Term: If you hold for more than one year, gains are taxed at preferential rates of 0%, 15%, or 20%, depending on your income irs.gov.
Losses: Capital losses can offset capital gains. You can also deduct up to $3,000 in capital losses against your ordinary income each year, with the remainder carried forward to future years.

Treatment 2: Gambling Income

If the DOJ successfully classifies prediction markets as gambling, the IRS would likely follow suit. This is generally the least favorable outcome for a profitable trader.

Tax Rate: All net winnings are taxed as ordinary income (up to 37%). The concept of a long-term holding period does not exist.
Losses: This is the biggest drawback. You can only deduct gambling losses to the extent of your gambling winnings from the same year. You cannot use gambling losses to offset other income (like your salary), and you cannot carry unused losses forward to future years. Furthermore, these losses must be taken as an itemized deduction on Schedule A.

Treatment 3: Section 1256 Contracts

This treatment is the "holy grail" for many traders, primarily argued for positions on CFTC-regulated platforms like Kalshi. Under Section 1256 of the Internal Revenue Code, certain regulated futures and options contracts receive special tax treatment.

Tax Rate (The 60/40 Rule): Regardless of how long you hold the contract, 60% of the gain or loss is treated as long-term, and 40% is treated as short-term. This creates a blended rate that is significantly lower than the top ordinary income rate.
Mark-to-Market: Section 1256 contracts must be "marked to market" at year-end, meaning any open positions are treated as if they were sold for their fair market value on the last business day of the year.
The Catch: While Kalshi operates as a CFTC-Designated Contract Market (DCM), the IRS has never officially confirmed that its specific binary event contracts qualify for Section 1256 treatment everydaycpe.com. Taking this position carries a degree of audit risk.

Tax Treatment Comparison

Feature	Capital Gains	Gambling Income	Section 1256 Contracts
Tax Rate	0%/15%/20% (long-term) or ordinary rates (short-term)	Ordinary income rates (up to 37%)	Blended 60% long-term / 40% short-term rate
Loss Treatment	Offsets capital gains + up to $3,000 against ordinary income. Excess can be carried forward.	Deductible only against gambling winnings. No carryforward. Must itemize.	Offsets other 1256 gains. Net loss can be carried back 3 years.
Reporting Forms	Form 8949, Schedule D	Schedule 1 (Form 1040), Schedule A	Form 6781
Primary Platform	Polymarket (as crypto asset trades)	PredictIt (issues 1099-MISC)	Kalshi (arguable, not confirmed)

How a DOJ Gambling Classification Could Force the IRS's Hand

The IRS and DOJ operate independently, but a definitive legal ruling from one often influences the other. If the DOJ successfully prosecutes a prediction market platform under federal gambling laws, it would be extremely difficult for the IRS to maintain that the activity constitutes financial derivatives trading for tax purposes.

An official "gambling" classification would provide the IRS with the legal cover it needs to issue clear, and likely unfavorable, guidance for traders. This could lead to:

Reclassification of Income: The IRS could formally state that all prediction market profits are to be reported as gambling income, invalidating the capital gains and Section 1256 approaches.
Increased Enforcement: With a clear legal standing, the IRS could launch a compliance campaign targeting prediction market traders, using on-chain data and information requests to platforms to identify non-compliant taxpayers.
Potential for Back Taxes: The most worrying outcome for traders would be if the IRS applies this new interpretation retroactively, potentially subjecting traders to audits, back taxes, penalties, and interest for prior years where they reported using a different method.

Platform Risk: Tax Implications for Kalshi vs. Polymarket

The DOJ investigation highlights the distinct risks associated with different platforms.

Kalshi

Kalshi's entire legal and business model is built on its status as a CFTC-regulated DCM pm.wiki. Its primary defense against the gambling allegation is that it offers financial instruments, not wagers.

Tax Position: The strongest argument for Section 1256 treatment exists for Kalshi traders.
Investigation Impact: A DOJ gambling classification would directly undermine Kalshi's regulatory foundation and the basis for claiming Section 1256 treatment.
Reporting: While Kalshi is regulated, it does not currently provide a comprehensive Form 1099-B covering all event contract trades predictionhunt.com. This means users are still responsible for tracking their own cost basis and P&L, a task that can be complex.

Polymarket

As a decentralized, crypto-based platform, Polymarket operates in a different paradigm. It does not rely on a specific U.S. regulatory license for its core international protocol.

Tax Position: The default treatment is capital gains, as every trade involves swapping one crypto asset (USDC) for another (a market outcome token).
Investigation Impact: A gambling classification would represent a major shift from how most users currently handle their taxes. It would force them to transition from tracking capital gains on Form 8949 to reporting gambling income.
Reporting: Polymarket issues no tax forms whatsoever pm.wiki. The reporting burden is 100% on the user. Every single trade on the Polygon blockchain must be tracked, its cost basis calculated, and the resulting gain or loss determined. This is a monumental task to perform manually.

For Polymarket traders, the lack of official reporting makes using dedicated crypto tax software essential. Platforms like dTax can connect directly to your public wallet address, automatically import your entire transaction history, and calculate the capital gains and losses for each trade. This provides an indispensable, audit-ready record, regardless of how the tax treatment ultimately evolves.

What Should Traders Do Now? Reporting Amidst Uncertainty

With the DOJ probe underway, filing your taxes as a prediction market trader is more fraught than ever. While no one can predict the outcome, here are prudent steps to take now.

Prioritize Meticulous Record-Keeping: Now more than ever, you must have a perfect record of every trade. This includes the date, the asset traded, the quantity, the cost basis in USD, and the proceeds. This data is your ultimate defense in an audit.
Leverage Tax Software: Manually tracking hundreds or thousands of on-chain trades is a recipe for error. For platforms like Polymarket, using a crypto tax calculator like dTax is non-negotiable. It automates the painful process of data aggregation and gain/loss calculation. For centralized platforms like Kalshi, you can use dTax's universal CSV import feature to upload your trade history and consolidate all your trading activity in one place.
Discuss Your Reporting Position with a Professional: The path you choose—capital gains, Section 1256, or gambling income—depends on the platform you used, the facts of your situation, and your personal risk tolerance.
- An aggressive position, like claiming Section 1256 treatment for Kalshi, may offer the biggest tax savings but carries the highest audit risk. Some professionals might suggest filing a Form 8275 Disclosure Statement to protect against certain penalties if the IRS disagrees with your position everydaycpe.com.
- A conservative position might involve treating winnings as "Other Income," paying a higher tax rate now to minimize future risk.
Consult a Qualified Tax Professional: This guidance is not tax advice. The DOJ investigation has raised the stakes significantly. It is imperative to consult with a tax professional who has expertise in cryptocurrency, derivatives, and the evolving regulatory landscape before filing your return.

Frequently Asked Questions

If the DOJ decides prediction markets are gambling, do I have to amend my past tax returns?

This is the key question for many traders. The answer depends on what action the IRS takes following a DOJ decision. The IRS may issue guidance that is only forward-looking, meaning it applies only to the current and future tax years. However, the IRS could also decide to apply the interpretation retroactively, which could trigger audits for past returns. If you are concerned about your reporting position on prior-year returns, you should discuss the possibility of filing an amended return with your tax advisor.

What's the difference between a 1099-B, 1099-MISC, and no form at all?

The type of tax form you receive (or don't receive) gives a strong hint about how the platform expects you to report your income.

Form 1099-B: Issued by brokerages for sales of securities or derivatives. It reports proceeds and often cost basis, and the data maps directly to Form 8949 for capital gains reporting.
Form 1099-MISC: Used to report miscellaneous income. PredictIt, for example, issues this form for net winnings over $600 pm.wiki. This income is typically reported on Schedule 1 and taxed at ordinary income rates.
No Form: Platforms like Polymarket provide no tax documentation. This means the entire responsibility for tracking, calculating, and reporting your taxable income falls on you.

Can I use dTax to handle my prediction market taxes?

Yes. For on-chain prediction markets like Polymarket, dTax can sync with your wallet to automatically import all your trades and calculate the associated capital gains and losses. For centralized platforms that provide a trade history export, you can use our flexible CSV importer to upload your data. This allows you to consolidate all your prediction market activity with your other crypto transactions—from DeFi to NFTs—to generate a comprehensive and accurate tax report.